Welcome! We are the research group of Jen Dionne, Associate Professor of Materials Science and Engineering at Stanford University. We are a diverse team of materials scientists, chemists, applied physicists, electrical engineers, chemical engineers, and mechanical engineers.

Through the design of new optical materials and microscopies, we observe chemical and biological processes as they unfold with nanometer scale resolution. We then use these observations to improve energy-relevant processes (such as photocatalysis and energy storage) and medical diagnostics and therapeutics.

Latest News

January 29: Congratulations to David on his paper, “Broadband and wide-angle nonreciprocity with a non-Hermitian metamaterial,” published in Physical Review B! Article

January 8: Congratulations to Diane and Michelle on their paper, “Chemically Responsive Elastomers Exhibiting Unity-Order Refractive Index Modulation,” now published in Advanced Materials! Article

January 6: Chris is awarded a Kodak Research Fellowship. Congratulations Chris!

December 25: Congratulations to our alum, Dr. Tarun Narayan on his wedding!

December 19: Congratulations to Randy on his latest paper, “Nanomaterials for in vivo Imaging of Mechanical Forces and Electrical Fields,” now published in Nature Review Materials! Article

December 1: Jen presents at the Frontiers of Electroceramics workshop at MIT. Thank you Harry Tuller for the invitation!

November 26: David, Alice, Katherine and Jen attend the Materials Research Society Fall Meeting in Boston!

November 20: Jen gives an invited talk at the School of Engineering retreat. Thank you Dean Widom for the invitation!

November 8: Jen is named one of the 2017 Moore Inventor Fellows! The press release is here.

November 7: Stefan, Randy, Alice and Jen attend the SHIFT 2017 Conference in Tenerife, Spain. Congratulations to Alice on winning the best oral presentation award in the bio session!

Featured Research

I. Metamaterials for Broadband Nonreciprocity:

David and co-authors have designed a metamaterial capable of acting as a diode over a broad spectral and angular range. Utilizing the extreme bandstructure tunability in Parity-Time symmetric plasmonic metamaterials, we show nonreciprocal transmission over a 50 nm and 60 degree range in the visible. These findings lay the groundwork for multiplexed optical diodes, nonreciprocal flat lenses with negative indices, and unidirectional invisibility cloaking. The work is now published in Physical Review B!

II. Nanomaterials for in vivo Imaging of Mechanical Forces and Electrical Fields:

Mechanical forces and electrical fields are crucial for cellular signaling and can be both inducers and indicators of disease. Randy and co-authors wrote a review highlighting recent advances in nanoscale, in vivo, optical probes, discussing spatial and temporal resolution, stability and stimuli sensitivity in bioimaging. The review is now published in Nature Reviews Materials!

III. Hot carriers enable new upconversion scheme:

Guru and co-authors have demonstrated a new upconversion scheme that combines plasmonic nanoparticles with semiconducting quantum wells. By overcomimg the small absorption cross sections and narrow linewidths of traditional upconverters, this scheme could improve upconversion efficiencies toward 50%. Using a system of Au/Ag disks on GaN/InGaN, light is upconverted from 500 to 440 nm as hot electrons and holes are injected into the quantum well. The system shows a size- and wavelength- dependence corresponding to the metal plasmon resonance and a linear power dependence. This work is now published online in Nano Letters!